Transcript Engineering Test Facility

NLC - The Next Linear Collider
Engineering Test Facility
What is it and what does it do?
Paul Czarapata
NLC - The Next Linear Collider
What is the ETF?
• An Engineering Test Facility
– The Delay Line Distribution System (DLDS) represents a major
technical challenge for the NLC. The ETF will be used to explore
and refine the DLDS.
– The Linac structures are spaced approximately 56m apart. The
ETF will allow the installation details of the structures, support
girders, permanent magnets and ancillary electronics to be
developed for use in a “real” linac.
– The later addition of a photoinjector could allow the transport and
acceleration of beam for Wakefield and other physics studies. (C.
Bohn’s area)
Paul Czarapata
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NLC - The Next Linear Collider
Where is the ETF?
• Meson
– Given the required length ( 400m) for one subsection of the main linac,
the only contiguous, straight tunnel sections available were in Meson.
• Meson Polarized (MP) or Meson West (MW)
– MW has the Beams Division Cryogenics department located in MW9 and
the upstream tunnels are scheduled to be used for VLHC string tests.
– MP has CMS activities currently underway in the MP9 hall but for the
immediate future, this does not represent a conflict.
– In its final form, the ETF would stretch from the 1200’ area upstream of
the Detector Building to nearly the end of the MP9 hall.
Paul Czarapata
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NLC - The Next Linear Collider
Why do we need an ETF?
• DLDS
– The DLDS waveguide is an x-band distribution system using over-moded
waveguide and selective mode taps to deliver power to the linac
structures. Calculations show that the waveguide is extremely sensitive to
deformation. This will require the development of support hardware to
minimize stresses on the waveguide.
– The high power RF (600MW pulses) precludes the use of windows
between the accelerating structures and the RF waveguide. This implies
the waveguide will see machine vacuum levels. Handling, cleaning, and
certifying the waveguide are all details needing work.
• How does one connect the waveguide sections?
– The waveguide is currently planned to be 7 inches in diameter. The
number of connections needed in a full length machine would require an
extreme number of vacuum tight flanges. Alternative methods of coupling
sections together will be explored.
Paul Czarapata
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NLC - The Next Linear Collider
What else?
• Structures from Technical Division require processing
– The accelerating structures need to be power conditioned and measured
prior to installation. The ETF will be an area where 150MW of RF will be
available to condition the structures.
– The structures also need to be mounted on support girders with auxiliary
beam monitoring and transport magnets. The ETF will serve as an
integration test area for these tasks.
• Development of the Control system and Machine protection systems
can take place here.
• Development of Vacuum system.
Paul Czarapata
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NLC - The Next Linear Collider
What are we doing this year?
• In the next few weeks a “marching army” will begin the clean-out of
MP-7 and MP-8
• When a mechanical engineer is lured into the ETF, work will begin on
waveguide supports and section welding.
– A major task will be developing the waveguide welding scheme. The
longest section of waveguide is 400m long! With 160 km of waveguide
the use of flanges is cost prohibitive and could be a major detriment to the
vacuum system reliability.
• Ralph Pasquinelli and Ding Sun have established the following items
as goals for the RF work for FY01:
Paul Czarapata
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NLC - The Next Linear Collider
Questions?
• We have a ton of them!
Paul Czarapata
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